Ex 16.3, 5
A fair coin with 1 marked on one face and 6 on the other and a fair die are both tossed. Find the probability that the sum of numbers that turn up is
(i) 3
If the coin is tossed we get only 1 or 6
If a die is thrown we get 1, 2, 3, 4, 5, 6
Hence,
S = (1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6),﷮ (6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6, 6)﷯﷯
n(S) = 12
Let A be the event sum 3
Hence A = {(1, 2)}
n(A) = 1
Probability of getting sum as 3 = P(A)
= n(A)﷮n(S)﷯
= 𝟏﷮𝟏𝟐﷯
Ex 16.3, 5
A fair coin with 1 marked on one face and 6 on the other and a fair die are both tossed. Find the probability that the sum of numbers that turn up is
(ii) 12
Let B be the event sum is 12.
Hence
B = {(6, 6)}
n(B) = 1
Probability of getting sum as 12 = P(B)
= n(B)﷮n(S)﷯
= 𝟏﷮𝟏𝟐﷯